Evaporator assembly for refrigeration appliance

ABSTRACT

The present invention relates to an evaporator assembly for use in a refrigeration appliance. The evaporator assembly of the present invention has a casing for accommodating an evaporator. The casing has on its inner surface a protrusion abutting against an opposing surface thereof. The protrusion has a sufficient strength to withstand a pressure exerted by a foam material which cures during an assembly process. In addition, the protrusion does not obstruct installation of the evaporator into the casing. The present invention also relates to a manufacturing process of a refrigeration appliance. The manufacturing process of the present invention comprises a step of installing the evaporator into the casing and a subsequent step of injecting foam material between an outer case of the refrigeration appliance and an outer surface of the casing.

The present invention relates to an evaporator assembly for use in arefrigeration appliance, in particular a no-frost domestic refrigerator.The present invention also relates to a process of manufacturing therefrigeration appliance by using the evaporator assembly.

The no-frost technology is an effective method of reducing humidity in arefrigeration compartment in order to prevent formation of frost on aninner case of the refrigeration compartment and on the articles storedtherein. A refrigeration appliance utilizing the no-frost technologygenerally includes an air circulation facility along which the airinside the refrigeration compartment is conveyed by means of a fantowards the evaporator and subsequently discharged into therefrigeration compartment. In the no-frost refrigeration appliance theevaporator of the refrigeration circuit is disposed at a locationoutside the refrigeration compartment usually in a rear partition of theinner case which has an air inlet and an air outlet for the circulationof the air. Thereby, the moisture in the circulated air freezes on thesurface of the evaporator as the refrigerant evaporates. During thecirculation of the air, heat is also transferred with the circulated airfrom the articles stored in the refrigerating compartment to theevaporator through convection. As the moisture in the circulated airfreezes on the surface of the evaporator, the proper functioning of theevaporator starts degrading. Therefore, the evaporator must beeventually defrosted.

In general, the refrigeration compartment must be thermally insulatedfrom an outside in order to improve the refrigeration performance.Therefore, a region between the inner case of the refrigerationcompartment and the outer case of the refrigeration appliance is filledwith foam material, in particular polyurethane.

JPH0849965 (A) discloses a refrigerator which has an evaporator locatedin a rear partition of the refrigeration compartment. A gap between theinner case of the refrigeration apartment and the outer case of therefrigerator is filled with foam material.

A problem with the foam material is that during the curing process, thefoam material exerts pressure on the inner case and on the outer casesuch that the plastic elements thereof start deforming. If the innercase is permanently deformed when the foam material is completely cured,it becomes impossible to properly install the evaporator into thepartition.

In a commonly known technique spacers are utilized to preventdeformation of the plastic elements during the curing process. After thefoam is completely cured, the spacers are removed and the evaporator isinstalled. However, the assembly process of the evaporator becomes morecomplicated after the gaps have been filled with the foam material.Moreover, a thermal insulation performance degrades when the foammaterial is damaged during the assembly process of the evaporator.

An objective of the present invention is to provide an evaporatorassembly and a refrigeration appliance having the same which overcomesthe aforementioned drawbacks of the prior art and which enables an easyand a reliable installation of the evaporator. Another objective of thepresent invention is to provide a process of manufacturing therefrigeration appliance by using the evaporator assembly of the presentinvention.

This objective have been achieved by the evaporator assembly as definedin claim 1, the manufacturing process as defined in claim 11, and therefrigeration appliance as defined in claim 12. Further achievementshave been attained by the subject-matters respectively defined in thedependent claims.

The evaporator assembly of the present invention has a casing foraccommodating an evaporator. The casing has a front cover and a rearcover which are detachably attachable. The front cover forms a portionof an inner case of the refrigeration compartment. The rear cover has onits inner surface a protrusion which firmly abuts against an opposingsurface of the front cover. A cross-section and a material of theprotrusion is configured to exhibit a sufficient strength to withstandwithout being deformed, a pressure exerted by a curing foam materialwhich is injected between the outer surface of the rear cover and theouter case during an assembly process. In addition, the protrusion isformed on an inner surface of the rear cover at a position which doesnot obstruct installation of the evaporator.

The present invention also provides a process of manufacturing therefrigeration appliance by using the evaporator assembly. In themanufacturing process of the refrigeration appliance the evaporator isinstalled into the casing from an open side of the rear cover. Then, therear cover is attached to the front cover. Subsequently, foam materialis injected between the outer surface of the rear cover and the outercase.

In an embodiment, the protrusion has a mounting portion for detachablyattaching the evaporator to the rear cover. With the protrusion havingthe mounting portion, the evaporator can be secured to the casing andsimultaneously protected from possible damages during the foamingprocess. Thereby, an inner structure of the casing has been simplified.The circulation of air through he casing has been improved.

In alternative embodiment, the casing is provided in addition to theprotrusion with a separate mounting portion for detachably attaching theevaporator to the rear cover.

By virtue of the evaporator assembly of the present invention, theevaporator can be installed into the casing without interference withthe protrusion which prevents deformation of the cover during the curingof the foam material. The thermal insulation can be formed by foammaterial in a state where the evaporator has been already installed intothe casing. Thereby, the manufacturing process of the refrigerationappliance has been simplified and a high quality thermal insulation hasbeen attained. The casing has been effectively protected fromdeformations through the curing foam material during the manufacturingprocess. Thereby, the evaporator has been protected from damages. Thus,the proper installation of the evaporator has been maintained aftercompletion of the foaming process.

Additional advantages of the evaporator assembly of the presentinvention and the manufacturing process of the refrigeration applianceby using the evaporator assembly of the present invention will becomeapparent with the detailed description of the embodiments with referenceto the accompanying drawings in which:

FIG. 1—is a schematic partial perspective view of a refrigerationappliance having an evaporator assembly according to an embodiment ofthe present invention;

FIG. 2—is a schematic partial side view of the refrigeration appliancehaving the evaporator assembly shown in FIG. 1;

FIG. 3—is a schematic partial perspective view of the evaporatorassembly attached to an inner case of a refrigeration compartment shownin FIGS. 1 and 2;

FIG. 4—is a schematic partial side view of the evaporator assemblyattached to the inner case of the refrigeration compartment shown inFIG. 3;

FIG. 5—is a schematic cross sectional view of the evaporator assemblyattached to the inner case of the refrigeration compartment shown inFIG. 4, taken along the line A-A;

FIG. 6—is a schematic enlarged view of the detail B shown in FIG. 5;

FIG. 7—is a schematic perspective inner view of a rear cover of theevaporator assembly according to an embodiment of the present invention;

FIG. 8—is another schematic perspective inner view of the rear cover ofthe evaporator assembly according to an embodiment of the presentinvention;

FIG. 9—is a schematic perspective outer view of the rear cover of theevaporator assembly according to an embodiment of the present invention;

FIG. 10—is a schematic perspective view of an evaporator used in theevaporator assembly shown in FIGS. 1 to 6;

The reference signs appearing on the drawings relate to the followingtechnical features.

-   1. Evaporator assembly-   2. Refrigeration appliance-   3. Inner case-   3′ Inner case-   3″ Inner case-   3′″ Inner case-   4. Refrigeration compartment-   4′ Refrigeration compartment-   4″ Refrigeration compartment-   4′″ Refrigeration compartment-   5. Outer case-   6. Casing-   7. Evaporator-   8. Front cover-   9. Rear cover-   9 a. Inner surface-   9 b. Outer surface-   10. Protrusion-   11. Mounting portion-   12. Resilient leg-   13. Recess-   14. Reinforcement rib-   15. Open side-   16. Seat-   17. Counterpart seat-   18. Tube inlet-   19. Tube outlet-   20. Cable throughlet-   21. Power cable-   22. Discharge outlet-   23. Heater

The evaporator assembly (1) is suitable for use in a refrigerationappliance (2), in particular a domestic refrigerator (FIGS. 1 and 2).

The refrigeration appliance (2) comprises an inner case (3) and an outercase (5). The inner case (3) forms a refrigeration compartment (4). Theouter case (5) forms a body of the refrigeration appliance (2). Therefrigeration appliance (2) further comprises an evaporator assembly (1)(FIGS. 1 to 9).

The evaporator assembly (1) of the present invention comprises a casing(6) for accommodating an evaporator (7) for refrigerating therefrigeration compartment (2). The casing (6) has an air inlet (notshown) and an air outlet (not shown) for circulating the air inside therefrigeration compartment (2) via the evaporator (7) by means of a fan(not shown). The casing (6) has a front cover (8) and a rear cover (9)which are detachably attachable to each other. The front cover (8) formsa portion of an inner case (3). The rear cover (9) has on its innersurface (9 a) a protrusion (10) which firmly abuts against an opposingsurface of the front cover (8). A cross-section and a material of theprotrusion (10) is configured to exhibit a sufficient strength towithstand without being deformed, a pressure exerted by a curing foammaterial which is injected between the outer surface (9 b) of the rearcover (9) and the outer case (5) during an assembly process. Theprotrusion (10) is formed at a position on said inner surface (9 a) soas not to obstruct installation of the evaporator (7) at a designatedmounting position inside the casing (6) (FIGS. 1 to 9).

In an embodiment, the protrusion (10) has a mounting portion (11) fordetachably attaching the evaporator (7) to the rear cover (9) (FIGS. 5to 9).

In another embodiment, the mounting portion (11) has two resilient legs(12) each having an arc-shaped recess (13). The arc-shaped recesses (13)are formed to oppose each other and snap-fittingly engage with arefrigerant conveying tube of the evaporator (7). The resilient legs(12) are configured to firmly abut against the surface of the frontcover (8). In a version of this embodiment, the resilient legs (12) eachhave a tapered tip which form a V-shaped groove which narrows towards amiddle of the arc-shaped recesses (FIGS. 5 to 9).

In another embodiment, the protrusion (10) is integrally provided withthe rear cover (9) (FIGS. 5 to 9).

In another embodiment, the protrusion (10) is formed at position whichis at a mid-width and a mid-height of the rear cover (9) or in the closevicinity thereof (FIGS. 5 to 9).

In another embodiment, an outer surface (9 b) of the rear cover (9) isprovided with a plurality of reinforcement ribs (14) (FIG. 9).

In another embodiment, the rear cover (9) is provided in form of arectangular-shaped shell. The shell has an open side (15) which isconfigured to face the front cover (8). The shell has also a seat (16)which is formed around said open side (15) to circumferentially abutagainst a counterpart seat (17) which is formed on the front cover (8)(FIGS. 5 to 9).

In another embodiment, the front cover (8) is integrally provided withthe inner case (3) (FIG. 5). In this embodiment, the air inlet (notshown) and the air outlet (not shown) are formed into the front cover(8).

In another embodiment, the rear cover (9) has a tube inlet (18) and atube outlet (19) for respectively inserting an incoming tube and anoutgoing tube of the evaporator (7). In this embodiment, the rear cover(9) has also a cable throughlet (20) for inserting a electrical powertransmission cable (21) of an electrical defrost heater (23) attached tothe evaporator (7). In this embodiment, the rear cover (9) has also adischarge outlet (22) for discharging defrost water (FIGS. 8 to 9).

In another embodiment, the cable throughlet (20) is formed close to anupper side of the rear cover (9) and the discharge outlet (22) is formedon a lowest side of the rear cover (9) (FIGS. 8 to 9).

In another embodiment, the front cover (8), the rear cover (9), and theprotrusion (10) are made of plastic material.

The present invention also provides a process of manufacturing arefrigeration appliance (2) using the evaporator assembly (1). In themanufacturing process of the present invention the evaporator (7) isinstalled into the casing (6) from an open side (15) of the rear cover(9). Then, the rear cover (9) is attached to the front cover (8). Then,foam material is injected between the outer surface (9 b) of the rearcover (9) and the outer case (5). These steps are carried out in theabove given order.

In another embodiment, refrigeration appliance (2) has an evaporator (7)which has a meandering refrigerant conveying tube (FIG. 10). In aversion of this embodiment, the evaporator (7) is provided with fins(not shown).

In another embodiment, the evaporator (7) is provided with an electricaldefrost heater (23). In an alternative embodiment, a hot gas defrosttechnique is utilized. In this alternative embodiment the electricaldefrost heater (23) is omitted.

By virtue of the evaporator assembly (1) of the present invention, theproper installation of the evaporator (7) has been maintained during andafter completion of the foaming process, a high quality thermalinsulation has been attained, and the manufacturing process of therefrigeration appliance (2) has been simplified.

1. An evaporator assembly for use in a refrigeration appliance, inparticular a domestic refrigerator comprising: an inner case which formsa refrigeration compartment; an outer case which forms a body of therefrigeration appliance, a casing for accommodating an evaporator forrefrigerating the refrigeration compartment, wherein the casing has anair inlet and an air outlet for circulating the air inside therefrigeration compartment via the evaporator by means of a fan, whereinsaid casing has a front cover and a rear cover which are detachablyattachable to each other, wherein the front cover forms a portion of aninner case, and the rear cover has on its inner surface a protrusionwhich firmly abuts against an opposing surface of the front cover,wherein a cross-section and a material of the protrusion is configuredto exhibit a sufficient strength to withstand without being deformed, apressure exerted by a curing foam material which is injected between theouter surface of the rear cover and the outer case during an assemblyprocess, and wherein the protrusion is formed at a position on saidinner surface so as not to obstruct installation of the evaporator at adesignated mounting position inside the casing.
 2. The evaporatorassembly according to claim 1, wherein the protrusion has a mountingportion for detachably attaching the evaporator to the rear cover. 3.The evaporator assembly according to claim 2, wherein the mountingportion has two resilient legs each having an arc-shaped recess whichare formed to oppose each other, wherein the arc-shaped recesses areconfigured to snap-fittingly engage with a refrigerant conveying tube ofthe evaporator, and wherein the resilient legs are configured to firmlyabut against the surface of the front cover.
 4. The evaporator assemblyaccording to claim 1, wherein the protrusion is integrally provided withthe rear cover.
 5. The evaporator assembly according to claim 1, whereinthe protrusion is formed at position which is at a mid-width and amid-height of the rear cover or in a close vicinity thereof.
 6. Theevaporator assembly according to claim 1, wherein an outer surface ofthe rear cover is provided with a plurality of reinforcement ribs. 7.The evaporator assembly according to claim 1, wherein the rear cover isprovided in form of a rectangular-shaped shell which has: an open sidewhich is configured to face the front cover; and a seat which is formedaround said open side to circumferentially abut against a counterpartseat formed on the front cover.
 8. The evaporator assembly according toclaim 1, wherein the front cover is integrally provided with the innercase, wherein the air inlet and the air outlet are formed in to thefront cover.
 9. The evaporator assembly according to claim 1, whereinthe rear cover having a tube inlet and a tube outlet for respectivelyinserting an incoming tube and an outgoing tube of the evaporator; acable throughlet for inserting a electrical power transmission cable ofan electrical defrost heater attached to the evaporator and a dischargeoutlet for discharging defrost water.
 10. The evaporator assemblyaccording to claim 9, wherein the cable throughlet is formed close to anupper side of the rear cover and the discharge outlet is formed on alowest side of the rear cover.
 11. A process of manufacturing arefrigeration appliance using the evaporator assembly as defined inclaim 1, the manufacturing process comprising the steps of: installingthe evaporator into the casing, attaching the rear cover to the frontcover and injecting foam material between the outer surface of the rearcover and the outer case.
 12. A refrigeration appliance, in particular adomestic refrigerator comprising an inner case which forms arefrigeration compartment; and an outer case which forms a body of therefrigeration appliance, comprising an evaporator assembly as defined inclaim
 1. 13. The refrigeration appliance according to claim 12, whereinan evaporator which has a meandering refrigerant conveying tube.
 14. Therefrigeration appliance according to claim 13, wherein the evaporator isprovided with fins.
 15. The refrigeration appliance according to claim13, wherein the evaporator is provided with an electrical defrostheater.